Effect of the Deformation during Pressure Welding of a Wrought EP975 Nickel Alloy and a Single-Crystal Intermetallic VKNA-25 Alloy on the Structure and Properties of the Welded Joints
Abstract
The influence of the strain (24, 30, 40%) during the pressure welding (PW) of an EP975 alloy in a superplasticity state and subsequent high-temperature heat treatment of welded joints on their structure and room-temperature mechanical properties is studied to find the conditions of PW of a single-crystal [001] Ni3Al-based VKNA-25 blade alloy and an EP975 disk alloy in order to fabricate a blisk. The tensile strength of the welded samples is found to be maximal after PW of the EP975 alloy at a strain of ~40%, and the strength reached at lower strains is also sufficiently high, 0.7-0.8 of the strength of the VKNA-25 blade alloy. To optimize the technology of solid-phase joining, it is reasonable to decrease the PW strain to 20% and to increase the welding temperature to 1175°C.
- Publication:
-
Russian Metallurgy
- Pub Date:
- December 2019
- DOI:
- 10.1134/S0036029519110041
- Bibcode:
- 2019RuMet2019.1195D
- Keywords:
-
- solid-phase joining;
- superplasticity;
- pressure welding;
- strain;
- wrought nickel superalloy;
- cast intermetallic alloy;
- single crystal;
- structure;
- diffusion;
- properties